from flask import jsonify
from validataclass.validators import DataclassValidator

from tofu_api.common.rest import BaseMethodView
from .task_handler import TaskHandler
from .validators import TaskCreateData, TaskUpdateData


class TaskBaseView(BaseMethodView):
    """
    Base class for view classes for the `/tasks` endpoint.
    """

    task_handler: TaskHandler

    def __init__(self, *, task_handler: TaskHandler):
        self.task_handler = task_handler


class TaskCollectionView(TaskBaseView):
    """
    View class for `/api/tasks` endpoint.
    """

    # Validators
    task_create_validator = DataclassValidator(TaskCreateData)

    def get(self):
        """
        Get list of all tasks.
        """
        task_list = self.task_handler.fetch_all_tasks()
        return jsonify({
            'items': [task.to_dict() for task in task_list],
            'total_count': len(task_list),
        }), 200

    def post(self):
        """
        Create a new task.
        """
        # Parse request data
        create_data: TaskCreateData = self.validate_request_data(self.task_create_validator)

        # Create new task
        new_task = self.task_handler.create_task(create_data)

        # Return new task as JSON
        return jsonify(new_task.to_dict()), 201


class TaskItemView(TaskBaseView):
    """
    View class for `/api/tasks/<int:task_id>` endpoint.
    """

    # Validators
    task_update_validator = DataclassValidator(TaskUpdateData)

    def get(self, task_id: int):
        """
        Get a single task by ID.
        """
        task = self.task_handler.fetch_task(task_id)
        return jsonify(task.to_dict()), 200

    def patch(self, task_id: int):
        """
        Update a single task by ID.
        """
        # Parse request data
        update_data: TaskUpdateData = self.validate_request_data(self.task_update_validator)

        # Fetch task and update
        task = self.task_handler.fetch_task(task_id)
        task = self.task_handler.update_task(task, update_data)

        # Return updated task as JSON
        return jsonify(task.to_dict()), 200

    def delete(self, task_id: int):
        """
        Delete a single task by ID.
        """
        # Fetch task and delete
        task = self.task_handler.fetch_task(task_id)
        self.task_handler.delete_task(task)

        return self.empty_response()